Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
593 FXUS66 KSGX 110944 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 244 AM PDT Sat May 11 2024 .SYNOPSIS... Areas of night and morning low clouds and fog will continue across portions of the coastal areas and valleys through the next week. Gradual warming inland will occur through Sunday followed by minor cooling Monday and Tuesday. Inland warming trend will likely resume the second half of next week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Marine layer low clouds have filled in across the coastal basin to the foothills of the mountains, busting any chance of viewing the aurora for most of us. Elsewhere, skies are clear. Low clouds will clear to the coast by late morning, though the beaches will likely remain cloudy into the afternoon. The upper level low currently centered over western Arizona will continue to drift east today and Sunday, allowing weak ridging to shift over So Cal. This will bring minor warming inland, with highs in the lower deserts reaching 100 degrees by Sunday. Highs will generally be several degrees above normal inland, but close to normal for the coastal areas and western valleys thanks to the persistent marine layer. The marine layer depth should lower through the weekend with the arrival of the ridge for less extensive low clouds each night and morning, but little to no clearing at the coast each day. The ridge shifts east on Monday as a weak closed low moves towards the region, slowly moving through on Tuesday and finally passing east by Wednesday. High temperatures will lower by a degree or two each day with a slight expansion of marine layer low cloud coverage each night. The pattern becomes more iffy beyond Wednesday as there continues to be much spread in the ensemble solutions regarding the position of the E Pac ridge and the potential for weak troughing somewhere in the vicinity of So Cal, or potentially even a long wave trough across the Western US for the latter part of the week. While there is a large range of possibilities for temperatures, the coldest solutions account for less than 15% of the ensemble space, while the warmest is about 30% and everything else lies somewhere in between. Current forecast high temps remain around the 50th percentile. Either way we`ll continue to see May Gray, it`s just a matter of how far inland clouds will extend each night. && .AVIATION... 110930Z...Coast/Valleys...Low clouds with bases 1200-1800 ft MSL, and tops 3000-3500 ft MSL covering much of the coasts and valleys this morning. Bases may lower by a few hundred feet at times through 15Z. Low clouds obscuring higher terrain, with VIS 1-3SM in fog where clouds and terrain intersect. Expect inland clearing 16Z-18Z and partial clearing at the coast by 18-19z. SCT-BKN low clouds could persist at the beaches into Sat afternoon. Low clouds look to push back inland between 00-03z Sun, reaching more of the coastal valleys by 06-09z. Mountains/Deserts...Mostly clear with unrestricted VIS through Sat morning. SCT/BKN clouds over the mountains with bases around 9000 ft MSL Sat afternoon. && .MARINE... No hazardous marine conditions are expected through Wednesday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ PUBLIC...SS AVIATION/MARINE...Adams